A series of experiments is proposed that systematically explores ethnic differences in the processes of emotional reactivity, emotional control, and emotional perception. Subjects will be young male and female African Americans, Chinese Americans, European Americans and Mexican Americans. Chinese Americans and Mexican Americans will be the first generation of their families born in the United States. Experiments will be conducted in a laboratory setting using a multi-method approach in which subjective experience (self-report of emotional state), expressive behavior (microanalytic and microanalytic observational coding) and autonomic and somatic nervous system physiology (monitoring of cardiovascular, electrodermal, somatic and respiratory activity) will be measured. The effects of socioeconomic status and acculturation will be determined in all experiments. To study emotional reactivity, a number of different stimuli will be used,some of which are more voluntary and internal to the subject (e.g., emotional memories and directed facial actions) and others that are more involuntary and external to the subject (acoustic startle and emotion- eliciting films). Several less emotional tasks (e.g., physical exercise) will be included to help isolate ethnic differences in emotional reactivity from possible ethnic differences in nonemotional reactivity. Whenever possible, multiple emotions will be sampled including anger, disgust, fear, happiness, sadness and surprise. To study emotional control, subjects will attempt to inhibit their emotional responses to an acoustic startle stimulus and to emotion-eliciting films. To study emotional perception, subjects will attempt to rate the feelings of another person who is engaged in a dyadic interactions. This research is motivated by suggestive empirical findings of ethnic differences in the realms of basic emotional processes and in vulnerability to emotion-related psychopathologies.